H. Schnyder et C. Bassetti, BILATERAL CONVERGENCE NYSTAGMUS IN UNILATERAL DORSAL MIDBRAIN STROKE DUE TO OCCLUSION OF THE SUPERIOR CEREBELLAR ARTERY, Neuro-ophthalmology, 16(1), 1996, pp. 59-63
The authors report a 33-year-old man with left dorsal pontomesencephal
ic and cerebellar infarction due to an angiographically verified left
superior cerebellar artery (SCA)-occlusion. Clinical presentation incl
uded dysarthria, homolateral limb ataxia, gait ataxia and controlatera
l spinothalamic sensory loss. Additionally, skew deviation, bilateral
convergence nystagmus and pseudo-sixth nerve palsy of the left eye wer
e observed. Vertical gaze and pupillary light reactions were preserved
. This observation expands the spectrum of eye movement abnormalities
due to midbrain involvement in isolated SCA-stroke and confirms a mese
ncephalic tectal territory of irrigation supplied by this artery. Addi
tionally, it might give further evidence for the hypothesis of premoto
r control of convergence at a higher than mesencephalic level.